Bladder outlet obstruction is typically attributed to either benign prostatic hyperplasia (BPH) or urethral stricture disease. BPH is one of the most common diseases found in aging men. It is associated with lower urinary tract symptoms that affect the quality of life by interfering with daily activities and normal sleep patterns. Symptomatic (clinical) BPH is present in approximately 26% of men in the fifth decade of life, 33% of men in the sixth decade, 41% of men in the seventh decade, and 46% of men in the eighth decade of life and beyond.
Urethral stricture disease is a scarring of the urethra that is much less common, affecting less than 1% of the U.S. population, yet there are relatively few specialists in the country who surgically treat this disease. Surgeons who treat urethral stricture disease are typically based in large urban centers, meaning there could be a significant geographic distance separating patients from these specialists. Urethral strictures, or scar tissue, can lead to the narrowing and blockage of the urethra. Urethral stricture disease (USD) can affect up to 0.6% of the U.S. patient population, with more than 1.5 million office visits due to urethral strictures occurring between 1992 and 2000. In 2000, the U.S. economic burden associated with USD was nearly $200 M, excluding medication costs. Diagnosing USD increases health care expenditures by more than $6,000 per patient per year and patient personal expenditures for the disease are estimated between $16,000 and $17,000. Further, there are a limited number of urethral stricture surgeons and specialists across the U.S., so patients must frequently travel to a clinic for surgery and/or follow-up tests. Due to this inconvenience, approximately 24% of USD patients will miss work for additional hospital and/or clinic visits. Likewise, there is a less than 15% follow-up rate within 6 months of the procedure.
Traditionally, BPH and USD are diagnosed using standardized questionnaires about urinary symptoms, along with uroflowmetry data, which measures urinary flow rate per time. Uroflowmetry is commonly used in urology offices for diagnosis, as well as for follow up of patients that undergo surgical or medical intervention for urinary outlet obstruction. Standard uroflowmetry machines are relatively expensive and are typically available only in urology offices. Therefore, there is a need for cost-effective systems, devices, and methods that can be used by patients remotely, as well in urology offices, to provide accurate urine data for BPH and USD diagnosis.